Squares and parallelograms create the illusion of cubes, using three shades. The cubes resemble steps. They are big and dramatic. When seen at full-size, viewers love or hate this illusion. Some can’t bear to look at it because they are disturbed by it and think they will fall. Pythagoras’ Theorem is used to work out the relative sizes of the squares and parallelograms. The length of the diagonal of a square is always approximately 1.4 times the length of the side of the square.
The afghan in the photo was made in Aran weight yarn. Any yarn can be used. It should be in three shades which give the effect of light and shadow on the cube. Diagonally knit squares work well with variegated yarns as they give some interesting patterns.